A memory device having a three-dimensional structure has been proposed in which memory holes are made in a stacked body in which inter-electrode insulating films are multiply stacked alternately with electrode films that function as control gates of memory cells, and silicon bodies used to form channels are provided on the side walls of the memory holes with a charge storage film interposed between the silicon bodies and the side walls.
The memory holes are made by etching the multiple electrode films and the multiple insulating films. In such a case, when step etching is performed by switching the etching gas between the electrode film and the insulating film, there is a risk of problems such as the processing time increasing and the control of the patterned configuration of the holes being difficult. Moreover, in the case where etching is performed unselectively and collectively by using the same gas for the electrode films and the insulating films, there is a risk that the holes may extend through to the layers under the stacked body.